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1 /*
2  * Copyright (C) 2006 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.os;
18 
19 import android.annotation.TestApi;
20 import android.net.LocalSocket;
21 import android.net.LocalSocketAddress;
22 import android.system.Os;
23 import android.system.OsConstants;
24 import android.util.Log;
25 import com.android.internal.os.Zygote;
26 import dalvik.system.VMRuntime;
27 import java.io.BufferedWriter;
28 import java.io.DataInputStream;
29 import java.io.IOException;
30 import java.io.OutputStreamWriter;
31 import java.nio.charset.StandardCharsets;
32 import java.util.ArrayList;
33 import java.util.Arrays;
34 import java.util.List;
35 
36 /*package*/ class ZygoteStartFailedEx extends Exception {
ZygoteStartFailedEx(String s)37     ZygoteStartFailedEx(String s) {
38         super(s);
39     }
40 
ZygoteStartFailedEx(Throwable cause)41     ZygoteStartFailedEx(Throwable cause) {
42         super(cause);
43     }
44 
ZygoteStartFailedEx(String s, Throwable cause)45     ZygoteStartFailedEx(String s, Throwable cause) {
46         super(s, cause);
47     }
48 }
49 
50 /**
51  * Tools for managing OS processes.
52  */
53 public class Process {
54     private static final String LOG_TAG = "Process";
55 
56     /**
57      * @hide for internal use only.
58      */
59     public static final String ZYGOTE_SOCKET = "zygote";
60 
61     /**
62      * @hide for internal use only.
63      */
64     public static final String SECONDARY_ZYGOTE_SOCKET = "zygote_secondary";
65 
66     /**
67      * Defines the root UID.
68      * @hide
69      */
70     public static final int ROOT_UID = 0;
71 
72     /**
73      * Defines the UID/GID under which system code runs.
74      */
75     public static final int SYSTEM_UID = 1000;
76 
77     /**
78      * Defines the UID/GID under which the telephony code runs.
79      */
80     public static final int PHONE_UID = 1001;
81 
82     /**
83      * Defines the UID/GID for the user shell.
84      * @hide
85      */
86     public static final int SHELL_UID = 2000;
87 
88     /**
89      * Defines the UID/GID for the log group.
90      * @hide
91      */
92     public static final int LOG_UID = 1007;
93 
94     /**
95      * Defines the UID/GID for the WIFI supplicant process.
96      * @hide
97      */
98     public static final int WIFI_UID = 1010;
99 
100     /**
101      * Defines the UID/GID for the mediaserver process.
102      * @hide
103      */
104     public static final int MEDIA_UID = 1013;
105 
106     /**
107      * Defines the UID/GID for the DRM process.
108      * @hide
109      */
110     public static final int DRM_UID = 1019;
111 
112     /**
113      * Defines the UID/GID for the group that controls VPN services.
114      * @hide
115      */
116     public static final int VPN_UID = 1016;
117 
118     /**
119      * Defines the UID/GID for the NFC service process.
120      * @hide
121      */
122     public static final int NFC_UID = 1027;
123 
124     /**
125      * Defines the UID/GID for the Bluetooth service process.
126      * @hide
127      */
128     public static final int BLUETOOTH_UID = 1002;
129 
130     /**
131      * Defines the GID for the group that allows write access to the internal media storage.
132      * @hide
133      */
134     public static final int MEDIA_RW_GID = 1023;
135 
136     /**
137      * Access to installed package details
138      * @hide
139      */
140     public static final int PACKAGE_INFO_GID = 1032;
141 
142     /**
143      * Defines the UID/GID for the shared RELRO file updater process.
144      * @hide
145      */
146     public static final int SHARED_RELRO_UID = 1037;
147 
148     /**
149      * Defines the UID/GID for the audioserver process.
150      * @hide
151      */
152     public static final int AUDIOSERVER_UID = 1041;
153 
154     /**
155      * Defines the UID/GID for the cameraserver process
156      * @hide
157      */
158     public static final int CAMERASERVER_UID = 1047;
159 
160     /**
161      * Defines the start of a range of UIDs (and GIDs), going from this
162      * number to {@link #LAST_APPLICATION_UID} that are reserved for assigning
163      * to applications.
164      */
165     public static final int FIRST_APPLICATION_UID = 10000;
166 
167     /**
168      * Last of application-specific UIDs starting at
169      * {@link #FIRST_APPLICATION_UID}.
170      */
171     public static final int LAST_APPLICATION_UID = 19999;
172 
173     /**
174      * First uid used for fully isolated sandboxed processes (with no permissions of their own)
175      * @hide
176      */
177     public static final int FIRST_ISOLATED_UID = 99000;
178 
179     /**
180      * Last uid used for fully isolated sandboxed processes (with no permissions of their own)
181      * @hide
182      */
183     public static final int LAST_ISOLATED_UID = 99999;
184 
185     /**
186      * Defines the gid shared by all applications running under the same profile.
187      * @hide
188      */
189     public static final int SHARED_USER_GID = 9997;
190 
191     /**
192      * First gid for applications to share resources. Used when forward-locking
193      * is enabled but all UserHandles need to be able to read the resources.
194      * @hide
195      */
196     public static final int FIRST_SHARED_APPLICATION_GID = 50000;
197 
198     /**
199      * Last gid for applications to share resources. Used when forward-locking
200      * is enabled but all UserHandles need to be able to read the resources.
201      * @hide
202      */
203     public static final int LAST_SHARED_APPLICATION_GID = 59999;
204 
205     /**
206      * Standard priority of application threads.
207      * Use with {@link #setThreadPriority(int)} and
208      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
209      * {@link java.lang.Thread} class.
210      */
211     public static final int THREAD_PRIORITY_DEFAULT = 0;
212 
213     /*
214      * ***************************************
215      * ** Keep in sync with utils/threads.h **
216      * ***************************************
217      */
218 
219     /**
220      * Lowest available thread priority.  Only for those who really, really
221      * don't want to run if anything else is happening.
222      * Use with {@link #setThreadPriority(int)} and
223      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
224      * {@link java.lang.Thread} class.
225      */
226     public static final int THREAD_PRIORITY_LOWEST = 19;
227 
228     /**
229      * Standard priority background threads.  This gives your thread a slightly
230      * lower than normal priority, so that it will have less chance of impacting
231      * the responsiveness of the user interface.
232      * Use with {@link #setThreadPriority(int)} and
233      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
234      * {@link java.lang.Thread} class.
235      */
236     public static final int THREAD_PRIORITY_BACKGROUND = 10;
237 
238     /**
239      * Standard priority of threads that are currently running a user interface
240      * that the user is interacting with.  Applications can not normally
241      * change to this priority; the system will automatically adjust your
242      * application threads as the user moves through the UI.
243      * Use with {@link #setThreadPriority(int)} and
244      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
245      * {@link java.lang.Thread} class.
246      */
247     public static final int THREAD_PRIORITY_FOREGROUND = -2;
248 
249     /**
250      * Standard priority of system display threads, involved in updating
251      * the user interface.  Applications can not
252      * normally change to this priority.
253      * Use with {@link #setThreadPriority(int)} and
254      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
255      * {@link java.lang.Thread} class.
256      */
257     public static final int THREAD_PRIORITY_DISPLAY = -4;
258 
259     /**
260      * Standard priority of the most important display threads, for compositing
261      * the screen and retrieving input events.  Applications can not normally
262      * change to this priority.
263      * Use with {@link #setThreadPriority(int)} and
264      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
265      * {@link java.lang.Thread} class.
266      */
267     public static final int THREAD_PRIORITY_URGENT_DISPLAY = -8;
268 
269     /**
270      * Standard priority of audio threads.  Applications can not normally
271      * change to this priority.
272      * Use with {@link #setThreadPriority(int)} and
273      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
274      * {@link java.lang.Thread} class.
275      */
276     public static final int THREAD_PRIORITY_AUDIO = -16;
277 
278     /**
279      * Standard priority of the most important audio threads.
280      * Applications can not normally change to this priority.
281      * Use with {@link #setThreadPriority(int)} and
282      * {@link #setThreadPriority(int, int)}, <b>not</b> with the normal
283      * {@link java.lang.Thread} class.
284      */
285     public static final int THREAD_PRIORITY_URGENT_AUDIO = -19;
286 
287     /**
288      * Minimum increment to make a priority more favorable.
289      */
290     public static final int THREAD_PRIORITY_MORE_FAVORABLE = -1;
291 
292     /**
293      * Minimum increment to make a priority less favorable.
294      */
295     public static final int THREAD_PRIORITY_LESS_FAVORABLE = +1;
296 
297     /**
298      * Default scheduling policy
299      * @hide
300      */
301     public static final int SCHED_OTHER = 0;
302 
303     /**
304      * First-In First-Out scheduling policy
305      * @hide
306      */
307     public static final int SCHED_FIFO = 1;
308 
309     /**
310      * Round-Robin scheduling policy
311      * @hide
312      */
313     public static final int SCHED_RR = 2;
314 
315     /**
316      * Batch scheduling policy
317      * @hide
318      */
319     public static final int SCHED_BATCH = 3;
320 
321     /**
322      * Idle scheduling policy
323      * @hide
324      */
325     public static final int SCHED_IDLE = 5;
326 
327     /**
328      * Reset scheduler choice on fork.
329      * @hide
330      */
331     public static final int SCHED_RESET_ON_FORK = 0x40000000;
332 
333     // Keep in sync with SP_* constants of enum type SchedPolicy
334     // declared in system/core/include/cutils/sched_policy.h,
335     // except THREAD_GROUP_DEFAULT does not correspond to any SP_* value.
336 
337     /**
338      * Default thread group -
339      * has meaning with setProcessGroup() only, cannot be used with setThreadGroup().
340      * When used with setProcessGroup(), the group of each thread in the process
341      * is conditionally changed based on that thread's current priority, as follows:
342      * threads with priority numerically less than THREAD_PRIORITY_BACKGROUND
343      * are moved to foreground thread group.  All other threads are left unchanged.
344      * @hide
345      */
346     public static final int THREAD_GROUP_DEFAULT = -1;
347 
348     /**
349      * Background thread group - All threads in
350      * this group are scheduled with a reduced share of the CPU.
351      * Value is same as constant SP_BACKGROUND of enum SchedPolicy.
352      * FIXME rename to THREAD_GROUP_BACKGROUND.
353      * @hide
354      */
355     public static final int THREAD_GROUP_BG_NONINTERACTIVE = 0;
356 
357     /**
358      * Foreground thread group - All threads in
359      * this group are scheduled with a normal share of the CPU.
360      * Value is same as constant SP_FOREGROUND of enum SchedPolicy.
361      * Not used at this level.
362      * @hide
363      **/
364     private static final int THREAD_GROUP_FOREGROUND = 1;
365 
366     /**
367      * System thread group.
368      * @hide
369      **/
370     public static final int THREAD_GROUP_SYSTEM = 2;
371 
372     /**
373      * Application audio thread group.
374      * @hide
375      **/
376     public static final int THREAD_GROUP_AUDIO_APP = 3;
377 
378     /**
379      * System audio thread group.
380      * @hide
381      **/
382     public static final int THREAD_GROUP_AUDIO_SYS = 4;
383 
384     /**
385      * Thread group for top foreground app.
386      * @hide
387      **/
388     public static final int THREAD_GROUP_TOP_APP = 5;
389 
390     public static final int SIGNAL_QUIT = 3;
391     public static final int SIGNAL_KILL = 9;
392     public static final int SIGNAL_USR1 = 10;
393 
394     private static long sStartElapsedRealtime;
395     private static long sStartUptimeMillis;
396 
397     /**
398      * State for communicating with the zygote process.
399      *
400      * @hide for internal use only.
401      */
402     public static class ZygoteState {
403         final LocalSocket socket;
404         final DataInputStream inputStream;
405         final BufferedWriter writer;
406         final List<String> abiList;
407 
408         boolean mClosed;
409 
ZygoteState(LocalSocket socket, DataInputStream inputStream, BufferedWriter writer, List<String> abiList)410         private ZygoteState(LocalSocket socket, DataInputStream inputStream,
411                 BufferedWriter writer, List<String> abiList) {
412             this.socket = socket;
413             this.inputStream = inputStream;
414             this.writer = writer;
415             this.abiList = abiList;
416         }
417 
connect(String socketAddress)418         public static ZygoteState connect(String socketAddress) throws IOException {
419             DataInputStream zygoteInputStream = null;
420             BufferedWriter zygoteWriter = null;
421             final LocalSocket zygoteSocket = new LocalSocket();
422 
423             try {
424                 zygoteSocket.connect(new LocalSocketAddress(socketAddress,
425                         LocalSocketAddress.Namespace.RESERVED));
426 
427                 zygoteInputStream = new DataInputStream(zygoteSocket.getInputStream());
428 
429                 zygoteWriter = new BufferedWriter(new OutputStreamWriter(
430                         zygoteSocket.getOutputStream()), 256);
431             } catch (IOException ex) {
432                 try {
433                     zygoteSocket.close();
434                 } catch (IOException ignore) {
435                 }
436 
437                 throw ex;
438             }
439 
440             String abiListString = getAbiList(zygoteWriter, zygoteInputStream);
441             Log.i("Zygote", "Process: zygote socket opened, supported ABIS: " + abiListString);
442 
443             return new ZygoteState(zygoteSocket, zygoteInputStream, zygoteWriter,
444                     Arrays.asList(abiListString.split(",")));
445         }
446 
matches(String abi)447         boolean matches(String abi) {
448             return abiList.contains(abi);
449         }
450 
close()451         public void close() {
452             try {
453                 socket.close();
454             } catch (IOException ex) {
455                 Log.e(LOG_TAG,"I/O exception on routine close", ex);
456             }
457 
458             mClosed = true;
459         }
460 
isClosed()461         boolean isClosed() {
462             return mClosed;
463         }
464     }
465 
466     /**
467      * The state of the connection to the primary zygote.
468      */
469     static ZygoteState primaryZygoteState;
470 
471     /**
472      * The state of the connection to the secondary zygote.
473      */
474     static ZygoteState secondaryZygoteState;
475 
476     /**
477      * Start a new process.
478      *
479      * <p>If processes are enabled, a new process is created and the
480      * static main() function of a <var>processClass</var> is executed there.
481      * The process will continue running after this function returns.
482      *
483      * <p>If processes are not enabled, a new thread in the caller's
484      * process is created and main() of <var>processClass</var> called there.
485      *
486      * <p>The niceName parameter, if not an empty string, is a custom name to
487      * give to the process instead of using processClass.  This allows you to
488      * make easily identifyable processes even if you are using the same base
489      * <var>processClass</var> to start them.
490      *
491      * @param processClass The class to use as the process's main entry
492      *                     point.
493      * @param niceName A more readable name to use for the process.
494      * @param uid The user-id under which the process will run.
495      * @param gid The group-id under which the process will run.
496      * @param gids Additional group-ids associated with the process.
497      * @param debugFlags Additional flags.
498      * @param targetSdkVersion The target SDK version for the app.
499      * @param seInfo null-ok SELinux information for the new process.
500      * @param abi non-null the ABI this app should be started with.
501      * @param instructionSet null-ok the instruction set to use.
502      * @param appDataDir null-ok the data directory of the app.
503      * @param zygoteArgs Additional arguments to supply to the zygote process.
504      *
505      * @return An object that describes the result of the attempt to start the process.
506      * @throws RuntimeException on fatal start failure
507      *
508      * {@hide}
509      */
start(final String processClass, final String niceName, int uid, int gid, int[] gids, int debugFlags, int mountExternal, int targetSdkVersion, String seInfo, String abi, String instructionSet, String appDataDir, String[] zygoteArgs)510     public static final ProcessStartResult start(final String processClass,
511                                   final String niceName,
512                                   int uid, int gid, int[] gids,
513                                   int debugFlags, int mountExternal,
514                                   int targetSdkVersion,
515                                   String seInfo,
516                                   String abi,
517                                   String instructionSet,
518                                   String appDataDir,
519                                   String[] zygoteArgs) {
520         try {
521             return startViaZygote(processClass, niceName, uid, gid, gids,
522                     debugFlags, mountExternal, targetSdkVersion, seInfo,
523                     abi, instructionSet, appDataDir, zygoteArgs);
524         } catch (ZygoteStartFailedEx ex) {
525             Log.e(LOG_TAG,
526                     "Starting VM process through Zygote failed");
527             throw new RuntimeException(
528                     "Starting VM process through Zygote failed", ex);
529         }
530     }
531 
532     /** retry interval for opening a zygote socket */
533     static final int ZYGOTE_RETRY_MILLIS = 500;
534 
535     /**
536      * Queries the zygote for the list of ABIS it supports.
537      *
538      * @throws ZygoteStartFailedEx if the query failed.
539      */
getAbiList(BufferedWriter writer, DataInputStream inputStream)540     private static String getAbiList(BufferedWriter writer, DataInputStream inputStream)
541             throws IOException {
542         // Each query starts with the argument count (1 in this case)
543         writer.write("1");
544         // ... followed by a new-line.
545         writer.newLine();
546         // ... followed by our only argument.
547         writer.write("--query-abi-list");
548         writer.newLine();
549         writer.flush();
550 
551         // The response is a length prefixed stream of ASCII bytes.
552         int numBytes = inputStream.readInt();
553         byte[] bytes = new byte[numBytes];
554         inputStream.readFully(bytes);
555 
556         return new String(bytes, StandardCharsets.US_ASCII);
557     }
558 
559     /**
560      * Sends an argument list to the zygote process, which starts a new child
561      * and returns the child's pid. Please note: the present implementation
562      * replaces newlines in the argument list with spaces.
563      *
564      * @throws ZygoteStartFailedEx if process start failed for any reason
565      */
zygoteSendArgsAndGetResult( ZygoteState zygoteState, ArrayList<String> args)566     private static ProcessStartResult zygoteSendArgsAndGetResult(
567             ZygoteState zygoteState, ArrayList<String> args)
568             throws ZygoteStartFailedEx {
569         try {
570             // Throw early if any of the arguments are malformed. This means we can
571             // avoid writing a partial response to the zygote.
572             int sz = args.size();
573             for (int i = 0; i < sz; i++) {
574                 if (args.get(i).indexOf('\n') >= 0) {
575                     throw new ZygoteStartFailedEx("embedded newlines not allowed");
576                 }
577             }
578 
579             /**
580              * See com.android.internal.os.ZygoteInit.readArgumentList()
581              * Presently the wire format to the zygote process is:
582              * a) a count of arguments (argc, in essence)
583              * b) a number of newline-separated argument strings equal to count
584              *
585              * After the zygote process reads these it will write the pid of
586              * the child or -1 on failure, followed by boolean to
587              * indicate whether a wrapper process was used.
588              */
589             final BufferedWriter writer = zygoteState.writer;
590             final DataInputStream inputStream = zygoteState.inputStream;
591 
592             writer.write(Integer.toString(args.size()));
593             writer.newLine();
594 
595             for (int i = 0; i < sz; i++) {
596                 String arg = args.get(i);
597                 writer.write(arg);
598                 writer.newLine();
599             }
600 
601             writer.flush();
602 
603             // Should there be a timeout on this?
604             ProcessStartResult result = new ProcessStartResult();
605 
606             // Always read the entire result from the input stream to avoid leaving
607             // bytes in the stream for future process starts to accidentally stumble
608             // upon.
609             result.pid = inputStream.readInt();
610             result.usingWrapper = inputStream.readBoolean();
611 
612             if (result.pid < 0) {
613                 throw new ZygoteStartFailedEx("fork() failed");
614             }
615             return result;
616         } catch (IOException ex) {
617             zygoteState.close();
618             throw new ZygoteStartFailedEx(ex);
619         }
620     }
621 
622     /**
623      * Starts a new process via the zygote mechanism.
624      *
625      * @param processClass Class name whose static main() to run
626      * @param niceName 'nice' process name to appear in ps
627      * @param uid a POSIX uid that the new process should setuid() to
628      * @param gid a POSIX gid that the new process shuold setgid() to
629      * @param gids null-ok; a list of supplementary group IDs that the
630      * new process should setgroup() to.
631      * @param debugFlags Additional flags.
632      * @param targetSdkVersion The target SDK version for the app.
633      * @param seInfo null-ok SELinux information for the new process.
634      * @param abi the ABI the process should use.
635      * @param instructionSet null-ok the instruction set to use.
636      * @param appDataDir null-ok the data directory of the app.
637      * @param extraArgs Additional arguments to supply to the zygote process.
638      * @return An object that describes the result of the attempt to start the process.
639      * @throws ZygoteStartFailedEx if process start failed for any reason
640      */
startViaZygote(final String processClass, final String niceName, final int uid, final int gid, final int[] gids, int debugFlags, int mountExternal, int targetSdkVersion, String seInfo, String abi, String instructionSet, String appDataDir, String[] extraArgs)641     private static ProcessStartResult startViaZygote(final String processClass,
642                                   final String niceName,
643                                   final int uid, final int gid,
644                                   final int[] gids,
645                                   int debugFlags, int mountExternal,
646                                   int targetSdkVersion,
647                                   String seInfo,
648                                   String abi,
649                                   String instructionSet,
650                                   String appDataDir,
651                                   String[] extraArgs)
652                                   throws ZygoteStartFailedEx {
653         synchronized(Process.class) {
654             ArrayList<String> argsForZygote = new ArrayList<String>();
655 
656             // --runtime-args, --setuid=, --setgid=,
657             // and --setgroups= must go first
658             argsForZygote.add("--runtime-args");
659             argsForZygote.add("--setuid=" + uid);
660             argsForZygote.add("--setgid=" + gid);
661             if ((debugFlags & Zygote.DEBUG_ENABLE_JNI_LOGGING) != 0) {
662                 argsForZygote.add("--enable-jni-logging");
663             }
664             if ((debugFlags & Zygote.DEBUG_ENABLE_SAFEMODE) != 0) {
665                 argsForZygote.add("--enable-safemode");
666             }
667             if ((debugFlags & Zygote.DEBUG_ENABLE_DEBUGGER) != 0) {
668                 argsForZygote.add("--enable-debugger");
669             }
670             if ((debugFlags & Zygote.DEBUG_ENABLE_CHECKJNI) != 0) {
671                 argsForZygote.add("--enable-checkjni");
672             }
673             if ((debugFlags & Zygote.DEBUG_GENERATE_DEBUG_INFO) != 0) {
674                 argsForZygote.add("--generate-debug-info");
675             }
676             if ((debugFlags & Zygote.DEBUG_ALWAYS_JIT) != 0) {
677                 argsForZygote.add("--always-jit");
678             }
679             if ((debugFlags & Zygote.DEBUG_NATIVE_DEBUGGABLE) != 0) {
680                 argsForZygote.add("--native-debuggable");
681             }
682             if ((debugFlags & Zygote.DEBUG_ENABLE_ASSERT) != 0) {
683                 argsForZygote.add("--enable-assert");
684             }
685             if (mountExternal == Zygote.MOUNT_EXTERNAL_DEFAULT) {
686                 argsForZygote.add("--mount-external-default");
687             } else if (mountExternal == Zygote.MOUNT_EXTERNAL_READ) {
688                 argsForZygote.add("--mount-external-read");
689             } else if (mountExternal == Zygote.MOUNT_EXTERNAL_WRITE) {
690                 argsForZygote.add("--mount-external-write");
691             }
692             argsForZygote.add("--target-sdk-version=" + targetSdkVersion);
693 
694             //TODO optionally enable debuger
695             //argsForZygote.add("--enable-debugger");
696 
697             // --setgroups is a comma-separated list
698             if (gids != null && gids.length > 0) {
699                 StringBuilder sb = new StringBuilder();
700                 sb.append("--setgroups=");
701 
702                 int sz = gids.length;
703                 for (int i = 0; i < sz; i++) {
704                     if (i != 0) {
705                         sb.append(',');
706                     }
707                     sb.append(gids[i]);
708                 }
709 
710                 argsForZygote.add(sb.toString());
711             }
712 
713             if (niceName != null) {
714                 argsForZygote.add("--nice-name=" + niceName);
715             }
716 
717             if (seInfo != null) {
718                 argsForZygote.add("--seinfo=" + seInfo);
719             }
720 
721             if (instructionSet != null) {
722                 argsForZygote.add("--instruction-set=" + instructionSet);
723             }
724 
725             if (appDataDir != null) {
726                 argsForZygote.add("--app-data-dir=" + appDataDir);
727             }
728 
729             argsForZygote.add(processClass);
730 
731             if (extraArgs != null) {
732                 for (String arg : extraArgs) {
733                     argsForZygote.add(arg);
734                 }
735             }
736 
737             return zygoteSendArgsAndGetResult(openZygoteSocketIfNeeded(abi), argsForZygote);
738         }
739     }
740 
741     /**
742      * Tries to establish a connection to the zygote that handles a given {@code abi}. Might block and retry if the
743      * zygote is unresponsive. This method is a no-op if a connection is already open.
744      *
745      * @hide
746      */
establishZygoteConnectionForAbi(String abi)747     public static void establishZygoteConnectionForAbi(String abi) {
748         try {
749             openZygoteSocketIfNeeded(abi);
750         } catch (ZygoteStartFailedEx ex) {
751             throw new RuntimeException("Unable to connect to zygote for abi: " + abi, ex);
752         }
753     }
754 
755     /**
756      * Tries to open socket to Zygote process if not already open. If
757      * already open, does nothing.  May block and retry.
758      */
openZygoteSocketIfNeeded(String abi)759     private static ZygoteState openZygoteSocketIfNeeded(String abi) throws ZygoteStartFailedEx {
760         if (primaryZygoteState == null || primaryZygoteState.isClosed()) {
761             try {
762                 primaryZygoteState = ZygoteState.connect(ZYGOTE_SOCKET);
763             } catch (IOException ioe) {
764                 throw new ZygoteStartFailedEx("Error connecting to primary zygote", ioe);
765             }
766         }
767 
768         if (primaryZygoteState.matches(abi)) {
769             return primaryZygoteState;
770         }
771 
772         // The primary zygote didn't match. Try the secondary.
773         if (secondaryZygoteState == null || secondaryZygoteState.isClosed()) {
774             try {
775             secondaryZygoteState = ZygoteState.connect(SECONDARY_ZYGOTE_SOCKET);
776             } catch (IOException ioe) {
777                 throw new ZygoteStartFailedEx("Error connecting to secondary zygote", ioe);
778             }
779         }
780 
781         if (secondaryZygoteState.matches(abi)) {
782             return secondaryZygoteState;
783         }
784 
785         throw new ZygoteStartFailedEx("Unsupported zygote ABI: " + abi);
786     }
787 
788     /**
789      * Returns elapsed milliseconds of the time this process has run.
790      * @return  Returns the number of milliseconds this process has return.
791      */
getElapsedCpuTime()792     public static final native long getElapsedCpuTime();
793 
794     /**
795      * Return the {@link SystemClock#elapsedRealtime()} at which this process was started.
796      */
getStartElapsedRealtime()797     public static final long getStartElapsedRealtime() {
798         return sStartElapsedRealtime;
799     }
800 
801     /**
802      * Return the {@link SystemClock#uptimeMillis()} at which this process was started.
803      */
getStartUptimeMillis()804     public static final long getStartUptimeMillis() {
805         return sStartUptimeMillis;
806     }
807 
808     /** @hide */
setStartTimes(long elapsedRealtime, long uptimeMillis)809     public static final void setStartTimes(long elapsedRealtime, long uptimeMillis) {
810         sStartElapsedRealtime = elapsedRealtime;
811         sStartUptimeMillis = uptimeMillis;
812     }
813 
814     /**
815      * Returns true if the current process is a 64-bit runtime.
816      */
is64Bit()817     public static final boolean is64Bit() {
818         return VMRuntime.getRuntime().is64Bit();
819     }
820 
821     /**
822      * Returns the identifier of this process, which can be used with
823      * {@link #killProcess} and {@link #sendSignal}.
824      */
myPid()825     public static final int myPid() {
826         return Os.getpid();
827     }
828 
829     /**
830      * Returns the identifier of this process' parent.
831      * @hide
832      */
myPpid()833     public static final int myPpid() {
834         return Os.getppid();
835     }
836 
837     /**
838      * Returns the identifier of the calling thread, which be used with
839      * {@link #setThreadPriority(int, int)}.
840      */
myTid()841     public static final int myTid() {
842         return Os.gettid();
843     }
844 
845     /**
846      * Returns the identifier of this process's uid.  This is the kernel uid
847      * that the process is running under, which is the identity of its
848      * app-specific sandbox.  It is different from {@link #myUserHandle} in that
849      * a uid identifies a specific app sandbox in a specific user.
850      */
myUid()851     public static final int myUid() {
852         return Os.getuid();
853     }
854 
855     /**
856      * Returns this process's user handle.  This is the
857      * user the process is running under.  It is distinct from
858      * {@link #myUid()} in that a particular user will have multiple
859      * distinct apps running under it each with their own uid.
860      */
myUserHandle()861     public static UserHandle myUserHandle() {
862         return UserHandle.of(UserHandle.getUserId(myUid()));
863     }
864 
865     /**
866      * Returns whether the given uid belongs to an application.
867      * @param uid A kernel uid.
868      * @return Whether the uid corresponds to an application sandbox running in
869      *     a specific user.
870      */
isApplicationUid(int uid)871     public static boolean isApplicationUid(int uid) {
872         return UserHandle.isApp(uid);
873     }
874 
875     /**
876      * Returns whether the current process is in an isolated sandbox.
877      * @hide
878      */
isIsolated()879     public static final boolean isIsolated() {
880         return isIsolated(myUid());
881     }
882 
883     /** {@hide} */
isIsolated(int uid)884     public static final boolean isIsolated(int uid) {
885         uid = UserHandle.getAppId(uid);
886         return uid >= FIRST_ISOLATED_UID && uid <= LAST_ISOLATED_UID;
887     }
888 
889     /**
890      * Returns the UID assigned to a particular user name, or -1 if there is
891      * none.  If the given string consists of only numbers, it is converted
892      * directly to a uid.
893      */
getUidForName(String name)894     public static final native int getUidForName(String name);
895 
896     /**
897      * Returns the GID assigned to a particular user name, or -1 if there is
898      * none.  If the given string consists of only numbers, it is converted
899      * directly to a gid.
900      */
getGidForName(String name)901     public static final native int getGidForName(String name);
902 
903     /**
904      * Returns a uid for a currently running process.
905      * @param pid the process id
906      * @return the uid of the process, or -1 if the process is not running.
907      * @hide pending API council review
908      */
getUidForPid(int pid)909     public static final int getUidForPid(int pid) {
910         String[] procStatusLabels = { "Uid:" };
911         long[] procStatusValues = new long[1];
912         procStatusValues[0] = -1;
913         Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues);
914         return (int) procStatusValues[0];
915     }
916 
917     /**
918      * Returns the parent process id for a currently running process.
919      * @param pid the process id
920      * @return the parent process id of the process, or -1 if the process is not running.
921      * @hide
922      */
getParentPid(int pid)923     public static final int getParentPid(int pid) {
924         String[] procStatusLabels = { "PPid:" };
925         long[] procStatusValues = new long[1];
926         procStatusValues[0] = -1;
927         Process.readProcLines("/proc/" + pid + "/status", procStatusLabels, procStatusValues);
928         return (int) procStatusValues[0];
929     }
930 
931     /**
932      * Returns the thread group leader id for a currently running thread.
933      * @param tid the thread id
934      * @return the thread group leader id of the thread, or -1 if the thread is not running.
935      *         This is same as what getpid(2) would return if called by tid.
936      * @hide
937      */
getThreadGroupLeader(int tid)938     public static final int getThreadGroupLeader(int tid) {
939         String[] procStatusLabels = { "Tgid:" };
940         long[] procStatusValues = new long[1];
941         procStatusValues[0] = -1;
942         Process.readProcLines("/proc/" + tid + "/status", procStatusLabels, procStatusValues);
943         return (int) procStatusValues[0];
944     }
945 
946     /**
947      * Set the priority of a thread, based on Linux priorities.
948      *
949      * @param tid The identifier of the thread/process to change.
950      * @param priority A Linux priority level, from -20 for highest scheduling
951      * priority to 19 for lowest scheduling priority.
952      *
953      * @throws IllegalArgumentException Throws IllegalArgumentException if
954      * <var>tid</var> does not exist.
955      * @throws SecurityException Throws SecurityException if your process does
956      * not have permission to modify the given thread, or to use the given
957      * priority.
958      */
setThreadPriority(int tid, int priority)959     public static final native void setThreadPriority(int tid, int priority)
960             throws IllegalArgumentException, SecurityException;
961 
962     /**
963      * Call with 'false' to cause future calls to {@link #setThreadPriority(int)} to
964      * throw an exception if passed a background-level thread priority.  This is only
965      * effective if the JNI layer is built with GUARD_THREAD_PRIORITY defined to 1.
966      *
967      * @hide
968      */
setCanSelfBackground(boolean backgroundOk)969     public static final native void setCanSelfBackground(boolean backgroundOk);
970 
971     /**
972      * Sets the scheduling group for a thread.
973      * @hide
974      * @param tid The identifier of the thread to change.
975      * @param group The target group for this thread from THREAD_GROUP_*.
976      *
977      * @throws IllegalArgumentException Throws IllegalArgumentException if
978      * <var>tid</var> does not exist.
979      * @throws SecurityException Throws SecurityException if your process does
980      * not have permission to modify the given thread, or to use the given
981      * priority.
982      * If the thread is a thread group leader, that is it's gettid() == getpid(),
983      * then the other threads in the same thread group are _not_ affected.
984      *
985      * Does not set cpuset for some historical reason, just calls
986      * libcutils::set_sched_policy().
987      */
setThreadGroup(int tid, int group)988     public static final native void setThreadGroup(int tid, int group)
989             throws IllegalArgumentException, SecurityException;
990 
991     /**
992      * Sets the scheduling group for a process and all child threads
993      * @hide
994      * @param pid The identifier of the process to change.
995      * @param group The target group for this process from THREAD_GROUP_*.
996      *
997      * @throws IllegalArgumentException Throws IllegalArgumentException if
998      * <var>tid</var> does not exist.
999      * @throws SecurityException Throws SecurityException if your process does
1000      * not have permission to modify the given thread, or to use the given
1001      * priority.
1002      *
1003      * group == THREAD_GROUP_DEFAULT means to move all non-background priority
1004      * threads to the foreground scheduling group, but to leave background
1005      * priority threads alone.  group == THREAD_GROUP_BG_NONINTERACTIVE moves all
1006      * threads, regardless of priority, to the background scheduling group.
1007      * group == THREAD_GROUP_FOREGROUND is not allowed.
1008      *
1009      * Always sets cpusets.
1010      */
setProcessGroup(int pid, int group)1011     public static final native void setProcessGroup(int pid, int group)
1012             throws IllegalArgumentException, SecurityException;
1013 
1014     /**
1015      * Return the scheduling group of requested process.
1016      *
1017      * @hide
1018      */
getProcessGroup(int pid)1019     public static final native int getProcessGroup(int pid)
1020             throws IllegalArgumentException, SecurityException;
1021 
1022     /**
1023      * On some devices, the foreground process may have one or more CPU
1024      * cores exclusively reserved for it. This method can be used to
1025      * retrieve which cores that are (if any), so the calling process
1026      * can then use sched_setaffinity() to lock a thread to these cores.
1027      * Note that the calling process must currently be running in the
1028      * foreground for this method to return any cores.
1029      *
1030      * The CPU core(s) exclusively reserved for the foreground process will
1031      * stay reserved for as long as the process stays in the foreground.
1032      *
1033      * As soon as a process leaves the foreground, those CPU cores will
1034      * no longer be reserved for it, and will most likely be reserved for
1035      * the new foreground process. It's not necessary to change the affinity
1036      * of your process when it leaves the foreground (if you had previously
1037      * set it to use a reserved core); the OS will automatically take care
1038      * of resetting the affinity at that point.
1039      *
1040      * @return an array of integers, indicating the CPU cores exclusively
1041      * reserved for this process. The array will have length zero if no
1042      * CPU cores are exclusively reserved for this process at this point
1043      * in time.
1044      */
getExclusiveCores()1045     public static final native int[] getExclusiveCores();
1046 
1047     /**
1048      * Set the priority of the calling thread, based on Linux priorities.  See
1049      * {@link #setThreadPriority(int, int)} for more information.
1050      *
1051      * @param priority A Linux priority level, from -20 for highest scheduling
1052      * priority to 19 for lowest scheduling priority.
1053      *
1054      * @throws IllegalArgumentException Throws IllegalArgumentException if
1055      * <var>tid</var> does not exist.
1056      * @throws SecurityException Throws SecurityException if your process does
1057      * not have permission to modify the given thread, or to use the given
1058      * priority.
1059      *
1060      * @see #setThreadPriority(int, int)
1061      */
setThreadPriority(int priority)1062     public static final native void setThreadPriority(int priority)
1063             throws IllegalArgumentException, SecurityException;
1064 
1065     /**
1066      * Return the current priority of a thread, based on Linux priorities.
1067      *
1068      * @param tid The identifier of the thread/process to change.
1069      *
1070      * @return Returns the current priority, as a Linux priority level,
1071      * from -20 for highest scheduling priority to 19 for lowest scheduling
1072      * priority.
1073      *
1074      * @throws IllegalArgumentException Throws IllegalArgumentException if
1075      * <var>tid</var> does not exist.
1076      */
getThreadPriority(int tid)1077     public static final native int getThreadPriority(int tid)
1078             throws IllegalArgumentException;
1079 
1080     /**
1081      * Return the current scheduling policy of a thread, based on Linux.
1082      *
1083      * @param tid The identifier of the thread/process to get the scheduling policy.
1084      *
1085      * @throws IllegalArgumentException Throws IllegalArgumentException if
1086      * <var>tid</var> does not exist, or if <var>priority</var> is out of range for the policy.
1087      * @throws SecurityException Throws SecurityException if your process does
1088      * not have permission to modify the given thread, or to use the given
1089      * scheduling policy or priority.
1090      *
1091      * {@hide}
1092      */
1093 
1094     @TestApi
getThreadScheduler(int tid)1095     public static final native int getThreadScheduler(int tid)
1096             throws IllegalArgumentException;
1097 
1098     /**
1099      * Set the scheduling policy and priority of a thread, based on Linux.
1100      *
1101      * @param tid The identifier of the thread/process to change.
1102      * @param policy A Linux scheduling policy such as SCHED_OTHER etc.
1103      * @param priority A Linux priority level in a range appropriate for the given policy.
1104      *
1105      * @throws IllegalArgumentException Throws IllegalArgumentException if
1106      * <var>tid</var> does not exist, or if <var>priority</var> is out of range for the policy.
1107      * @throws SecurityException Throws SecurityException if your process does
1108      * not have permission to modify the given thread, or to use the given
1109      * scheduling policy or priority.
1110      *
1111      * {@hide}
1112      */
1113 
setThreadScheduler(int tid, int policy, int priority)1114     public static final native void setThreadScheduler(int tid, int policy, int priority)
1115             throws IllegalArgumentException;
1116 
1117     /**
1118      * Determine whether the current environment supports multiple processes.
1119      *
1120      * @return Returns true if the system can run in multiple processes, else
1121      * false if everything is running in a single process.
1122      *
1123      * @deprecated This method always returns true.  Do not use.
1124      */
1125     @Deprecated
supportsProcesses()1126     public static final boolean supportsProcesses() {
1127         return true;
1128     }
1129 
1130     /**
1131      * Adjust the swappiness level for a process.
1132      *
1133      * @param pid The process identifier to set.
1134      * @param is_increased Whether swappiness should be increased or default.
1135      *
1136      * @return Returns true if the underlying system supports this
1137      *         feature, else false.
1138      *
1139      * {@hide}
1140      */
setSwappiness(int pid, boolean is_increased)1141     public static final native boolean setSwappiness(int pid, boolean is_increased);
1142 
1143     /**
1144      * Change this process's argv[0] parameter.  This can be useful to show
1145      * more descriptive information in things like the 'ps' command.
1146      *
1147      * @param text The new name of this process.
1148      *
1149      * {@hide}
1150      */
setArgV0(String text)1151     public static final native void setArgV0(String text);
1152 
1153     /**
1154      * Kill the process with the given PID.
1155      * Note that, though this API allows us to request to
1156      * kill any process based on its PID, the kernel will
1157      * still impose standard restrictions on which PIDs you
1158      * are actually able to kill.  Typically this means only
1159      * the process running the caller's packages/application
1160      * and any additional processes created by that app; packages
1161      * sharing a common UID will also be able to kill each
1162      * other's processes.
1163      */
killProcess(int pid)1164     public static final void killProcess(int pid) {
1165         sendSignal(pid, SIGNAL_KILL);
1166     }
1167 
1168     /** @hide */
setUid(int uid)1169     public static final native int setUid(int uid);
1170 
1171     /** @hide */
setGid(int uid)1172     public static final native int setGid(int uid);
1173 
1174     /**
1175      * Send a signal to the given process.
1176      *
1177      * @param pid The pid of the target process.
1178      * @param signal The signal to send.
1179      */
sendSignal(int pid, int signal)1180     public static final native void sendSignal(int pid, int signal);
1181 
1182     /**
1183      * @hide
1184      * Private impl for avoiding a log message...  DO NOT USE without doing
1185      * your own log, or the Android Illuminati will find you some night and
1186      * beat you up.
1187      */
killProcessQuiet(int pid)1188     public static final void killProcessQuiet(int pid) {
1189         sendSignalQuiet(pid, SIGNAL_KILL);
1190     }
1191 
1192     /**
1193      * @hide
1194      * Private impl for avoiding a log message...  DO NOT USE without doing
1195      * your own log, or the Android Illuminati will find you some night and
1196      * beat you up.
1197      */
sendSignalQuiet(int pid, int signal)1198     public static final native void sendSignalQuiet(int pid, int signal);
1199 
1200     /** @hide */
getFreeMemory()1201     public static final native long getFreeMemory();
1202 
1203     /** @hide */
getTotalMemory()1204     public static final native long getTotalMemory();
1205 
1206     /** @hide */
readProcLines(String path, String[] reqFields, long[] outSizes)1207     public static final native void readProcLines(String path,
1208             String[] reqFields, long[] outSizes);
1209 
1210     /** @hide */
getPids(String path, int[] lastArray)1211     public static final native int[] getPids(String path, int[] lastArray);
1212 
1213     /** @hide */
1214     public static final int PROC_TERM_MASK = 0xff;
1215     /** @hide */
1216     public static final int PROC_ZERO_TERM = 0;
1217     /** @hide */
1218     public static final int PROC_SPACE_TERM = (int)' ';
1219     /** @hide */
1220     public static final int PROC_TAB_TERM = (int)'\t';
1221     /** @hide */
1222     public static final int PROC_COMBINE = 0x100;
1223     /** @hide */
1224     public static final int PROC_PARENS = 0x200;
1225     /** @hide */
1226     public static final int PROC_QUOTES = 0x400;
1227     /** @hide */
1228     public static final int PROC_CHAR = 0x800;
1229     /** @hide */
1230     public static final int PROC_OUT_STRING = 0x1000;
1231     /** @hide */
1232     public static final int PROC_OUT_LONG = 0x2000;
1233     /** @hide */
1234     public static final int PROC_OUT_FLOAT = 0x4000;
1235 
1236     /** @hide */
readProcFile(String file, int[] format, String[] outStrings, long[] outLongs, float[] outFloats)1237     public static final native boolean readProcFile(String file, int[] format,
1238             String[] outStrings, long[] outLongs, float[] outFloats);
1239 
1240     /** @hide */
parseProcLine(byte[] buffer, int startIndex, int endIndex, int[] format, String[] outStrings, long[] outLongs, float[] outFloats)1241     public static final native boolean parseProcLine(byte[] buffer, int startIndex,
1242             int endIndex, int[] format, String[] outStrings, long[] outLongs, float[] outFloats);
1243 
1244     /** @hide */
getPidsForCommands(String[] cmds)1245     public static final native int[] getPidsForCommands(String[] cmds);
1246 
1247     /**
1248      * Gets the total Pss value for a given process, in bytes.
1249      *
1250      * @param pid the process to the Pss for
1251      * @return the total Pss value for the given process in bytes,
1252      *  or -1 if the value cannot be determined
1253      * @hide
1254      */
getPss(int pid)1255     public static final native long getPss(int pid);
1256 
1257     /**
1258      * Specifies the outcome of having started a process.
1259      * @hide
1260      */
1261     public static final class ProcessStartResult {
1262         /**
1263          * The PID of the newly started process.
1264          * Always >= 0.  (If the start failed, an exception will have been thrown instead.)
1265          */
1266         public int pid;
1267 
1268         /**
1269          * True if the process was started with a wrapper attached.
1270          */
1271         public boolean usingWrapper;
1272     }
1273 
1274     /**
1275      * Kill all processes in a process group started for the given
1276      * pid.
1277      * @hide
1278      */
killProcessGroup(int uid, int pid)1279     public static final native int killProcessGroup(int uid, int pid);
1280 
1281     /**
1282      * Remove all process groups.  Expected to be called when ActivityManager
1283      * is restarted.
1284      * @hide
1285      */
removeAllProcessGroups()1286     public static final native void removeAllProcessGroups();
1287 
1288     /**
1289      * Check to see if a thread belongs to a given process. This may require
1290      * more permissions than apps generally have.
1291      * @return true if this thread belongs to a process
1292      * @hide
1293      */
isThreadInProcess(int tid, int pid)1294     public static final boolean isThreadInProcess(int tid, int pid) {
1295         StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
1296         try {
1297             if (Os.access("/proc/" + tid + "/task/" + pid, OsConstants.F_OK)) {
1298                 return true;
1299             } else {
1300                 return false;
1301             }
1302         } catch (Exception e) {
1303             return false;
1304         } finally {
1305             StrictMode.setThreadPolicy(oldPolicy);
1306         }
1307 
1308     }
1309 }
1310